vex
get
puzzle
mystify
baffle
beat
pose
bewilder
flummox
stupefy
nonplus
gravel
amaze
dumbfound
confuse (generic term)
throw (generic term)
fox (generic term)
befuddle (generic term)
fuddle (generic term)
bedevil (generic term)
confound (generic term)
discombobulate (generic term)
puzzle over (related term)
puzzle out (related term)